1. Field of the Invention
The present invention relates to a method and a system for authenticating a Wireless Local Area Network (WLAN) terminal interworking with a Broadband Wireless Access (BWA) network.
2. Description of the Related Art
With the evolution of the technology in wireless data communication, wireless networks such as Institute of Electrical and Electronics Engineers (IEEE) 802.11a/b/g, 3rd-Generation (3G) High Speed Downlink Packet Access (HSDPA), Worldwide Interoperability for Microwave Access (Worldwide Interoperability for Microwave Access (WiMAX)), and Wireless Broadband (WiBro) using heterogeneous wireless technologies are configured, offering users a huge array of choices in wireless data service.
The usage of Wireless Local Area Network (WLAN) environments using unlicensed bandwidths is increasing, though not providing mobility, owing to relative advantages of several aspects such as connection costs.
Universal Mobile Telecommunication System-Wireless Local Area Network (UMTS-WLAN) interworking wireless routers for providing connectivity to Wireless Fidelity (WiFi) users in 3G networks have been already employed. In general, wireless routers supporting unlicensed bandwidth users under Internet Protocol version 4 (IPv4) environments all use a Network Address Translation (NAT) technology.
Network Address Translation (NAT) is a technology for sharing one or more public IP addresses among several users in consideration of a shortage of IP addresses such that the users can connect to a public network using one public IP address. That is, each of several Wireless Fidelity (WiFi) users is allocated one private IP address, and the Wireless Fidelity (WiFi) users may share one public IP address that is given to a router and connect to an Internet network.
To allow a plurality of users to share one public IP address, even translation for port information on Transmission Control Protocol (TCP)/User Datagram Protocol (UDP) should be performed. This is called IP masquerading in LINUX environments.